Air circulating fan



INVENTOR JOHN HBECKERT gimcg zr,

Arne/yew Patented Dec. 13, 1949 UNITED STATE S PATENT OFFICE 6 Claims.

This invention relates to air circulating fans and has as its object to provide a fan that is adapted to circulate air in all directions.

A specific object of the invention is to provide a fan adapted to deliver air from both the peripheral and the side areas thereof including the central or axial regions.

A further object of the invention i to provide a fan having a double impeller adapted to deliver air in substantially all directions to produce a movement of air generally similar to an expanding globe.

A further object of the invention is to provide a fan that is convertible from a pedestal type to a table type fan, said fan including a member which, in the pedestal arrangement, serves as a deflector for spreading laterally the air that would otherwise be delivered downwardly from the fan, and having the additional function of providing a base for the fan when it is converted into a table type fan.

Another object of the invention is to provide a fan that is adapted to deliver air in all directions except directly downwardly (the downward direction of delivery being obstructed by the base).

Other objects will become apparent in the ensuing specifications and appended drawings, in which:

Fig. 1 is a side view of a fan embodying my improved invention;

Fig. 2 is a sectional view through the hub of the fan showing the impeller in end elevation taken on the line 2-2 of Fig. 1;

Fig. 3 is a sectional view through the impeller taken on the line 3-3 of Fig. 1;

Fig. 4 is a side view of the impeller; and

Fig. 5 is a horizontal sectional view of the impeller taken on the line 5-5 of Fig. 4.

As an example of one form in which my in-' vention may be embodied, I have shown in the drawings an air circulating fan adapted to be employed for producing a gentle movement, in all directions, of air in a room or other confined air space. The fan has a pedestal including an upright 4 and a base 5 that is adapted to rest upon a floor surface. The upright 4 is tubular and supports an extension shaft 6 that is telescoped therein and is adapted to be secured in a plurality of adjusted positions by means of a hand screw 1 threaded through a boss 8 in the upright 4 and engaging the extension shaft. The upper end of the extension shaft Gis threaded into a boss 9 on an air deflector H. The deflector ll includes a bottom rim 12 that is provided with pads l3 by means of which it may be supported upon a fiat surface when the ped-' estal is detached therefrom, and a dome portion l0 that is generally conical and functions as a deflector to spread outwardly the currents of air moving downwardly from the fan impeller. Projecting upwardly from the deflector 'H is a post l4 on the upper end of which is supported outlet 25.

an electric motor l5. The motor 15 has a shaft 6| projecting from one end thereof, and a casing I6 which is provided with a bearing collar [1 in which the shaft BI is supported.

A fan impeller l8 has a tubular hub I9 provided therein with coaxial mounting rings 20 by means of which the impeller is mounted upon the shaft IS. The mounting rings 20 are joined to the tubular wall of the hub l9 by web members 2|.

The impeller l8 includes a plurality of double blades which are shaped so as to deliver air peripherally and axially in both directions. Each of these blades includes a pair of air ducts 23 each of which is shaped generally similar to a cornucopia and has an inlet 24 and an outlet 25. The inlets 24 of one pair of ducts are located in the forward face of a respective blade, whereas the outlets 25 of these ducts are located ahead of the forward face of a succeeding blade. At its inlet end, each duct 23 is flared or belled outwardly to a maximum cross-sectional area, and it gradually decreases in cross-sectional area from the inlet 24 to the outlet 25. The axis of each duct 23 is spinal-shaped, in a plane normal to the axis of the shaft l6, and gradually approaches the axis Hi from the inlet 24 to the The spiral axes of the ducts of one pair lie in common plane with the spiral axes of the ducts of the other pair. The inner end of each duct is extended into a space defined between the hub l9 and the outer, or inlet end of the other duct.

Radiating in an arc of somewhat more than 180 degrees from each pair of duct inlets 24 is a fan blade including a pair of opposed axially extending portions 26, a radially extendin peripheral portion 21, and curved intermediate portions 28 joining the peripheral portion 21 and the axially extending .portion 26. These several blade portions are swept rearwardly with reference to the direction of blade movement and collectively present a composite forward surface that is generally frusto-conical. That is, from the mouth 24, the blade portions 26 are inclined rearwardly and axially, the blade portion 21 is inclined rearwardly and radially outwardly, and the blade portions 28 are inclined rearwardly and in directions intermediate the axial and the radial. Consequently, the air encountered by the inclined surfaces will be thrown off the rotating blades in all directions throughout a substantially spherical surface of revolution of the fan impeller, be-

ginning with an axial direction away from the motor [6, as indicated by the arrow 29, thence radially outwardly as indicated by the arrow 30, and thence in an axial direction toward the motor 16 as indicated by the arrow 3|.

substantially axially of the fans axis of rotation.

The pairs of ducts 23 are joined by a median web wall 32 which extends to the hub l9.

In the operation of my improved air circulate ing fan, there will be an induction or inward movement of air into the center of the region swept by the impeller l8, along the periphery of the hub I 9. A portion of air thus brought to the center of the impeller will be scooped up lay the inlets 24 and forced through the ducts 23 to the outlets 25 thereof, from which it will be discharged circumferentially against the sloping sides of the blade portions 26 and thereby deflected axially outwardly (see Fig. 5). The remainder of the air indiic pd to the center of the impeller will be engaged by the fan blades and will be thrown outwardly in all directions by the portions 25, 2] and 18 of the fan blades respectively. Due to the reduction in cross-sectional area of the ducts 23 from the inlet to the outlet ends thereof, the air passing through these ducts will have its velocity accelerated. This tends to speed up the movement of'air discharged from the central regions of the fan, and provides for substantially as much movement of air in the ax ial regions encompassed within the extended periphery of the hub I9, as in the outer region's of air discharge from the impeller. Thus the in vention provides for a substantially uniform flow of air from the fan in all directions. This flow is comparatively gentlefsince the fan is not designed for'the projection of a high velocity concentrated air stream, but rather for a low velocity, creased air movement in all directions. This is a desirablecharacteristic in an air circulating fan for ventilating purposes;

The only'directi'on in'whi'ch the fan does not deliver air, is the downward direction, in which the air currents delivered from the fan are blocked by the deflector I I. Theseair currents are deflected outwardly as indicated by the arrows 3:6. K i

By detaching the shaft 6 from the boss 9, it is possible to set the deflector H- directly upon a table or the like surface, in which case the defiector becomes the basefor' the fan.

I claim as my invention:

1. In'an aircirculatirig fan, a motor having a shaft projecting from one end thereof, a fan impeller'having a pair of blades shaped to deliver air in all directions from the center of the impeller, and a pair of spiral air ducts for each blade, each pair of ducts having inlets'in theforward'face or one blade and outlets discharging ahead of the forward face of a succeeding blade.

2. In an air circulatin fan, a motor having a shaft projecting from one end thereof, a fan impeller having a pair of blades shaped to deliver air in all directions from the center of the impeller, and a pair of spiral air ducts for each blade, each pair of ducts having inlets in the forward face of one blade and outlets discharging ahead of the forward face of a succeeding blade, the blades having portions adapted to defleet the discharge from said outlets in opposite directions parallel to the axis of rotation of the impeller. f

3. In an air circulating fan, a motor having a shaft projec'ting'therefrom, impeller mounted upon said shaft, said impeller. comprising a plurality of blades and'a plurality of spiral air ducts arranged in symmetrical pair's, each pair of ducts having a pair of inlets in the forward face of one blade and a pair of outlets ahead of the forward face of a' succeeding blade, said impeller having a central web wall dividing theinlet ends of said ducts and blade portions entending axially and stanti'ally spiral passageways in said assembly,

each of which is provided with an inlet and an outlet; each inlet positioned in the forward side 9 e blad and t e utlet d s p s ja en the succeeding biade, there being one inlet in each blade; and means connecting the forward si e 9 a h bia t9 t m a s f rm n e 5inia as ew s! as wild? te mina djacent thesucceieding blade in a manner such that air will be discharged therefrom near the nt r of t e ee and was t longitudinal x of the fan assembly. W

1 an ai disc a m fan a driving motor Pr i ed w th a s aft hat e e e is ro one end theroff a fan assembly mounted on said shaft that comprises a plurality of blades, each blade ex ndin s bstan iall adial f s shaft and along the' major axis thereof and each proi d w th a new sid means to f m u ni all ta e ed sp ra assa n S sembly, each of which is provided with an inlet an a out e t at i smal e ha d' 'd inlets positioned in the forward side of one blade and said outlets positioned adjacent the forward i 9f t e eanlin blad an means ne t n th ewer; f e f ea blade to h s armin said as a a a d passagew r inat n ear th reward Sid f the succeeding blade so that air will be discharged r mm at a veloc t r a r t t a which it enters the inlet and paraill to the longitudinal axis of the fan assembly.

5.: e .31? imulat n a driving motor provided with a shaft that projects from one end he ee a n assembly i este on said f that comprises apluraiity of blades, each blade extending substantially radial-ly from said shaft an alon th ma e? axis t e f and each ovided with a forward side; means to form a pair of substantially tapered spiral passageways in said assembly, each passag'ewayprovided with an inlet andan cuti'et" that is smaller than the inlet, each inlet positioned in the forward side of" one bladeandeach outlet positioned adjacent the forward side of the succeeding blade; and ie es essent a the re s a blade with the means forming ea'chspiral passageway, said' passageway'terminating near the forward side of the succeeding blade in a manner such that air w'iil be discharged therefrom near and along the'i'ongitudinal axis oi said shaft and at a v elocity higher thaiitha-t at which it enters,

REFERENCES CITED e e wi'eg r tereeees re of e -9 n th file of this patent:

UNITED STATES PATENTS 

